/*
 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */
package javax.swing.text.html;

import java.io.*;
import java.util.Hashtable;
import javax.swing.text.AttributeSet;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyleContext;

/**
 * Constants used in the <code>HTMLDocument</code>.  These
 * are basically tag and attribute definitions.
 *
 * @author Timothy Prinzing
 * @author Sunita Mani
 */
public class HTML {

  /**
   * Typesafe enumeration for an HTML tag.  Although the
   * set of HTML tags is a closed set, we have left the
   * set open so that people can add their own tag types
   * to their custom parser and still communicate to the
   * reader.
   */
  public static class Tag {

    /**
     * @since 1.3
     */
    public Tag() {
    }

    /**
     * Creates a new <code>Tag</code> with the specified <code>id</code>,
     * and with <code>causesBreak</code> and <code>isBlock</code>
     * set to <code>false</code>.
     *
     * @param id the id of the new tag
     */
    protected Tag(String id) {
      this(id, false, false);
    }

    /**
     * Creates a new <code>Tag</code> with the specified <code>id</code>;
     * <code>causesBreak</code> and <code>isBlock</code> are defined
     * by the user.
     *
     * @param id the id of the new tag
     * @param causesBreak <code>true</code> if this tag causes a break to the flow of data
     * @param isBlock <code>true</code> if the tag is used to add structure to a document
     */
    protected Tag(String id, boolean causesBreak, boolean isBlock) {
      name = id;
      this.breakTag = causesBreak;
      this.blockTag = isBlock;
    }

    /**
     * Returns <code>true</code> if this tag is a block
     * tag, which is a tag used to add structure to a
     * document.
     *
     * @return <code>true</code> if this tag is a block tag, otherwise returns <code>false</code>
     */
    public boolean isBlock() {
      return blockTag;
    }

    /**
     * Returns <code>true</code> if this tag causes a
     * line break to the flow of data, otherwise returns
     * <code>false</code>.
     *
     * @return <code>true</code> if this tag causes a line break to the flow of data, otherwise
     * returns <code>false</code>
     */
    public boolean breaksFlow() {
      return breakTag;
    }

    /**
     * Returns <code>true</code> if this tag is pre-formatted,
     * which is true if the tag is either <code>PRE</code> or
     * <code>TEXTAREA</code>.
     *
     * @return <code>true</code> if this tag is pre-formatted, otherwise returns <code>false</code>
     */
    public boolean isPreformatted() {
      return (this == PRE || this == TEXTAREA);
    }

    /**
     * Returns the string representation of the
     * tag.
     *
     * @return the <code>String</code> representation of the tag
     */
    public String toString() {
      return name;
    }

    /**
     * Returns <code>true</code> if this tag is considered to be a paragraph
     * in the internal HTML model. <code>false</code> - otherwise.
     *
     * @return <code>true</code> if this tag is considered to be a paragraph in the internal HTML
     * model. <code>false</code> - otherwise.
     * @see HTMLDocument.HTMLReader.ParagraphAction
     */
    boolean isParagraph() {
      return (
          this == P
              || this == IMPLIED
              || this == DT
              || this == H1
              || this == H2
              || this == H3
              || this == H4
              || this == H5
              || this == H6
      );
    }

    boolean blockTag;
    boolean breakTag;
    String name;
    boolean unknown;

    // --- Tag Names -----------------------------------

    public static final Tag A = new Tag("a");
    public static final Tag ADDRESS = new Tag("address");
    public static final Tag APPLET = new Tag("applet");
    public static final Tag AREA = new Tag("area");
    public static final Tag B = new Tag("b");
    public static final Tag BASE = new Tag("base");
    public static final Tag BASEFONT = new Tag("basefont");
    public static final Tag BIG = new Tag("big");
    public static final Tag BLOCKQUOTE = new Tag("blockquote", true, true);
    public static final Tag BODY = new Tag("body", true, true);
    public static final Tag BR = new Tag("br", true, false);
    public static final Tag CAPTION = new Tag("caption");
    public static final Tag CENTER = new Tag("center", true, false);
    public static final Tag CITE = new Tag("cite");
    public static final Tag CODE = new Tag("code");
    public static final Tag DD = new Tag("dd", true, true);
    public static final Tag DFN = new Tag("dfn");
    public static final Tag DIR = new Tag("dir", true, true);
    public static final Tag DIV = new Tag("div", true, true);
    public static final Tag DL = new Tag("dl", true, true);
    public static final Tag DT = new Tag("dt", true, true);
    public static final Tag EM = new Tag("em");
    public static final Tag FONT = new Tag("font");
    public static final Tag FORM = new Tag("form", true, false);
    public static final Tag FRAME = new Tag("frame");
    public static final Tag FRAMESET = new Tag("frameset");
    public static final Tag H1 = new Tag("h1", true, true);
    public static final Tag H2 = new Tag("h2", true, true);
    public static final Tag H3 = new Tag("h3", true, true);
    public static final Tag H4 = new Tag("h4", true, true);
    public static final Tag H5 = new Tag("h5", true, true);
    public static final Tag H6 = new Tag("h6", true, true);
    public static final Tag HEAD = new Tag("head", true, true);
    public static final Tag HR = new Tag("hr", true, false);
    public static final Tag HTML = new Tag("html", true, false);
    public static final Tag I = new Tag("i");
    public static final Tag IMG = new Tag("img");
    public static final Tag INPUT = new Tag("input");
    public static final Tag ISINDEX = new Tag("isindex", true, false);
    public static final Tag KBD = new Tag("kbd");
    public static final Tag LI = new Tag("li", true, true);
    public static final Tag LINK = new Tag("link");
    public static final Tag MAP = new Tag("map");
    public static final Tag MENU = new Tag("menu", true, true);
    public static final Tag META = new Tag("meta");
    /*public*/ static final Tag NOBR = new Tag("nobr");
    public static final Tag NOFRAMES = new Tag("noframes", true, true);
    public static final Tag OBJECT = new Tag("object");
    public static final Tag OL = new Tag("ol", true, true);
    public static final Tag OPTION = new Tag("option");
    public static final Tag P = new Tag("p", true, true);
    public static final Tag PARAM = new Tag("param");
    public static final Tag PRE = new Tag("pre", true, true);
    public static final Tag SAMP = new Tag("samp");
    public static final Tag SCRIPT = new Tag("script");
    public static final Tag SELECT = new Tag("select");
    public static final Tag SMALL = new Tag("small");
    public static final Tag SPAN = new Tag("span");
    public static final Tag STRIKE = new Tag("strike");
    public static final Tag S = new Tag("s");
    public static final Tag STRONG = new Tag("strong");
    public static final Tag STYLE = new Tag("style");
    public static final Tag SUB = new Tag("sub");
    public static final Tag SUP = new Tag("sup");
    public static final Tag TABLE = new Tag("table", false, true);
    public static final Tag TD = new Tag("td", true, true);
    public static final Tag TEXTAREA = new Tag("textarea");
    public static final Tag TH = new Tag("th", true, true);
    public static final Tag TITLE = new Tag("title", true, true);
    public static final Tag TR = new Tag("tr", false, true);
    public static final Tag TT = new Tag("tt");
    public static final Tag U = new Tag("u");
    public static final Tag UL = new Tag("ul", true, true);
    public static final Tag VAR = new Tag("var");

    /**
     * All text content must be in a paragraph element.
     * If a paragraph didn't exist when content was
     * encountered, a paragraph is manufactured.
     * <p>
     * This is a tag synthesized by the HTML reader.
     * Since elements are identified by their tag type,
     * we create a some fake tag types to mark the elements
     * that were manufactured.
     */
    public static final Tag IMPLIED = new Tag("p-implied");

    /**
     * All text content is labeled with this tag.
     * <p>
     * This is a tag synthesized by the HTML reader.
     * Since elements are identified by their tag type,
     * we create a some fake tag types to mark the elements
     * that were manufactured.
     */
    public static final Tag CONTENT = new Tag("content");

    /**
     * All comments are labeled with this tag.
     * <p>
     * This is a tag synthesized by the HTML reader.
     * Since elements are identified by their tag type,
     * we create a some fake tag types to mark the elements
     * that were manufactured.
     */
    public static final Tag COMMENT = new Tag("comment");

    static final Tag allTags[] = {
        A, ADDRESS, APPLET, AREA, B, BASE, BASEFONT, BIG,
        BLOCKQUOTE, BODY, BR, CAPTION, CENTER, CITE, CODE,
        DD, DFN, DIR, DIV, DL, DT, EM, FONT, FORM, FRAME,
        FRAMESET, H1, H2, H3, H4, H5, H6, HEAD, HR, HTML,
        I, IMG, INPUT, ISINDEX, KBD, LI, LINK, MAP, MENU,
        META, NOBR, NOFRAMES, OBJECT, OL, OPTION, P, PARAM,
        PRE, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, S,
        STRONG, STYLE, SUB, SUP, TABLE, TD, TEXTAREA,
        TH, TITLE, TR, TT, U, UL, VAR
    };

    static {
      // Force HTMLs static initialize to be loaded.
      getTag("html");
    }
  }

  // There is no unique instance of UnknownTag, so we allow it to be
  // Serializable.
  public static class UnknownTag extends Tag implements Serializable {

    /**
     * Creates a new <code>UnknownTag</code> with the specified
     * <code>id</code>.
     *
     * @param id the id of the new tag
     */
    public UnknownTag(String id) {
      super(id);
    }

    /**
     * Returns the hash code which corresponds to the string
     * for this tag.
     */
    public int hashCode() {
      return toString().hashCode();
    }

    /**
     * Compares this object to the specified object.
     * The result is <code>true</code> if and only if the argument is not
     * <code>null</code> and is an <code>UnknownTag</code> object
     * with the same name.
     *
     * @param obj the object to compare this tag with
     * @return <code>true</code> if the objects are equal; <code>false</code> otherwise
     */
    public boolean equals(Object obj) {
      if (obj instanceof UnknownTag) {
        return toString().equals(obj.toString());
      }
      return false;
    }

    private void writeObject(java.io.ObjectOutputStream s)
        throws IOException {
      s.defaultWriteObject();
      s.writeBoolean(blockTag);
      s.writeBoolean(breakTag);
      s.writeBoolean(unknown);
      s.writeObject(name);
    }

    private void readObject(ObjectInputStream s)
        throws ClassNotFoundException, IOException {
      s.defaultReadObject();
      blockTag = s.readBoolean();
      breakTag = s.readBoolean();
      unknown = s.readBoolean();
      name = (String) s.readObject();
    }
  }

  /**
   * Typesafe enumeration representing an HTML
   * attribute.
   */
  public static final class Attribute {

    /**
     * Creates a new <code>Attribute</code> with the specified
     * <code>id</code>.
     *
     * @param id the id of the new <code>Attribute</code>
     */
    Attribute(String id) {
      name = id;
    }

    /**
     * Returns the string representation of this attribute.
     *
     * @return the string representation of this attribute
     */
    public String toString() {
      return name;
    }

    private String name;

    public static final Attribute SIZE = new Attribute("size");
    public static final Attribute COLOR = new Attribute("color");
    public static final Attribute CLEAR = new Attribute("clear");
    public static final Attribute BACKGROUND = new Attribute("background");
    public static final Attribute BGCOLOR = new Attribute("bgcolor");
    public static final Attribute TEXT = new Attribute("text");
    public static final Attribute LINK = new Attribute("link");
    public static final Attribute VLINK = new Attribute("vlink");
    public static final Attribute ALINK = new Attribute("alink");
    public static final Attribute WIDTH = new Attribute("width");
    public static final Attribute HEIGHT = new Attribute("height");
    public static final Attribute ALIGN = new Attribute("align");
    public static final Attribute NAME = new Attribute("name");
    public static final Attribute HREF = new Attribute("href");
    public static final Attribute REL = new Attribute("rel");
    public static final Attribute REV = new Attribute("rev");
    public static final Attribute TITLE = new Attribute("title");
    public static final Attribute TARGET = new Attribute("target");
    public static final Attribute SHAPE = new Attribute("shape");
    public static final Attribute COORDS = new Attribute("coords");
    public static final Attribute ISMAP = new Attribute("ismap");
    public static final Attribute NOHREF = new Attribute("nohref");
    public static final Attribute ALT = new Attribute("alt");
    public static final Attribute ID = new Attribute("id");
    public static final Attribute SRC = new Attribute("src");
    public static final Attribute HSPACE = new Attribute("hspace");
    public static final Attribute VSPACE = new Attribute("vspace");
    public static final Attribute USEMAP = new Attribute("usemap");
    public static final Attribute LOWSRC = new Attribute("lowsrc");
    public static final Attribute CODEBASE = new Attribute("codebase");
    public static final Attribute CODE = new Attribute("code");
    public static final Attribute ARCHIVE = new Attribute("archive");
    public static final Attribute VALUE = new Attribute("value");
    public static final Attribute VALUETYPE = new Attribute("valuetype");
    public static final Attribute TYPE = new Attribute("type");
    public static final Attribute CLASS = new Attribute("class");
    public static final Attribute STYLE = new Attribute("style");
    public static final Attribute LANG = new Attribute("lang");
    public static final Attribute FACE = new Attribute("face");
    public static final Attribute DIR = new Attribute("dir");
    public static final Attribute DECLARE = new Attribute("declare");
    public static final Attribute CLASSID = new Attribute("classid");
    public static final Attribute DATA = new Attribute("data");
    public static final Attribute CODETYPE = new Attribute("codetype");
    public static final Attribute STANDBY = new Attribute("standby");
    public static final Attribute BORDER = new Attribute("border");
    public static final Attribute SHAPES = new Attribute("shapes");
    public static final Attribute NOSHADE = new Attribute("noshade");
    public static final Attribute COMPACT = new Attribute("compact");
    public static final Attribute START = new Attribute("start");
    public static final Attribute ACTION = new Attribute("action");
    public static final Attribute METHOD = new Attribute("method");
    public static final Attribute ENCTYPE = new Attribute("enctype");
    public static final Attribute CHECKED = new Attribute("checked");
    public static final Attribute MAXLENGTH = new Attribute("maxlength");
    public static final Attribute MULTIPLE = new Attribute("multiple");
    public static final Attribute SELECTED = new Attribute("selected");
    public static final Attribute ROWS = new Attribute("rows");
    public static final Attribute COLS = new Attribute("cols");
    public static final Attribute DUMMY = new Attribute("dummy");
    public static final Attribute CELLSPACING = new Attribute("cellspacing");
    public static final Attribute CELLPADDING = new Attribute("cellpadding");
    public static final Attribute VALIGN = new Attribute("valign");
    public static final Attribute HALIGN = new Attribute("halign");
    public static final Attribute NOWRAP = new Attribute("nowrap");
    public static final Attribute ROWSPAN = new Attribute("rowspan");
    public static final Attribute COLSPAN = new Attribute("colspan");
    public static final Attribute PROMPT = new Attribute("prompt");
    public static final Attribute HTTPEQUIV = new Attribute("http-equiv");
    public static final Attribute CONTENT = new Attribute("content");
    public static final Attribute LANGUAGE = new Attribute("language");
    public static final Attribute VERSION = new Attribute("version");
    public static final Attribute N = new Attribute("n");
    public static final Attribute FRAMEBORDER = new Attribute("frameborder");
    public static final Attribute MARGINWIDTH = new Attribute("marginwidth");
    public static final Attribute MARGINHEIGHT = new Attribute("marginheight");
    public static final Attribute SCROLLING = new Attribute("scrolling");
    public static final Attribute NORESIZE = new Attribute("noresize");
    public static final Attribute ENDTAG = new Attribute("endtag");
    public static final Attribute COMMENT = new Attribute("comment");
    static final Attribute MEDIA = new Attribute("media");

    static final Attribute allAttributes[] = {
        FACE,
        COMMENT,
        SIZE,
        COLOR,
        CLEAR,
        BACKGROUND,
        BGCOLOR,
        TEXT,
        LINK,
        VLINK,
        ALINK,
        WIDTH,
        HEIGHT,
        ALIGN,
        NAME,
        HREF,
        REL,
        REV,
        TITLE,
        TARGET,
        SHAPE,
        COORDS,
        ISMAP,
        NOHREF,
        ALT,
        ID,
        SRC,
        HSPACE,
        VSPACE,
        USEMAP,
        LOWSRC,
        CODEBASE,
        CODE,
        ARCHIVE,
        VALUE,
        VALUETYPE,
        TYPE,
        CLASS,
        STYLE,
        LANG,
        DIR,
        DECLARE,
        CLASSID,
        DATA,
        CODETYPE,
        STANDBY,
        BORDER,
        SHAPES,
        NOSHADE,
        COMPACT,
        START,
        ACTION,
        METHOD,
        ENCTYPE,
        CHECKED,
        MAXLENGTH,
        MULTIPLE,
        SELECTED,
        ROWS,
        COLS,
        DUMMY,
        CELLSPACING,
        CELLPADDING,
        VALIGN,
        HALIGN,
        NOWRAP,
        ROWSPAN,
        COLSPAN,
        PROMPT,
        HTTPEQUIV,
        CONTENT,
        LANGUAGE,
        VERSION,
        N,
        FRAMEBORDER,
        MARGINWIDTH,
        MARGINHEIGHT,
        SCROLLING,
        NORESIZE,
        MEDIA,
        ENDTAG
    };
  }

  // The secret to 73, is that, given that the Hashtable contents
  // never change once the static initialization happens, the initial size
  // that the hashtable grew to was determined, and then that very size
  // is used.
  //
  private static final Hashtable<String, Tag> tagHashtable = new Hashtable<String, Tag>(73);

  /**
   * Maps from StyleConstant key to HTML.Tag.
   */
  private static final Hashtable<Object, Tag> scMapping = new Hashtable<Object, Tag>(8);

  static {

    for (int i = 0; i < Tag.allTags.length; i++) {
      tagHashtable.put(Tag.allTags[i].toString(), Tag.allTags[i]);
      StyleContext.registerStaticAttributeKey(Tag.allTags[i]);
    }
    StyleContext.registerStaticAttributeKey(Tag.IMPLIED);
    StyleContext.registerStaticAttributeKey(Tag.CONTENT);
    StyleContext.registerStaticAttributeKey(Tag.COMMENT);
    for (int i = 0; i < Attribute.allAttributes.length; i++) {
      StyleContext.registerStaticAttributeKey(Attribute.
          allAttributes[i]);
    }
    StyleContext.registerStaticAttributeKey(HTML.NULL_ATTRIBUTE_VALUE);
    scMapping.put(StyleConstants.Bold, Tag.B);
    scMapping.put(StyleConstants.Italic, Tag.I);
    scMapping.put(StyleConstants.Underline, Tag.U);
    scMapping.put(StyleConstants.StrikeThrough, Tag.STRIKE);
    scMapping.put(StyleConstants.Superscript, Tag.SUP);
    scMapping.put(StyleConstants.Subscript, Tag.SUB);
    scMapping.put(StyleConstants.FontFamily, Tag.FONT);
    scMapping.put(StyleConstants.FontSize, Tag.FONT);
  }

  /**
   * Returns the set of actual HTML tags that
   * are recognized by the default HTML reader.
   * This set does not include tags that are
   * manufactured by the reader.
   */
  public static Tag[] getAllTags() {
    Tag[] tags = new Tag[Tag.allTags.length];
    System.arraycopy(Tag.allTags, 0, tags, 0, Tag.allTags.length);
    return tags;
  }

  /**
   * Fetches a tag constant for a well-known tag name (i.e. one of
   * the tags in the set {A, ADDRESS, APPLET, AREA, B,
   * BASE, BASEFONT, BIG,
   * BLOCKQUOTE, BODY, BR, CAPTION, CENTER, CITE, CODE,
   * DD, DFN, DIR, DIV, DL, DT, EM, FONT, FORM, FRAME,
   * FRAMESET, H1, H2, H3, H4, H5, H6, HEAD, HR, HTML,
   * I, IMG, INPUT, ISINDEX, KBD, LI, LINK, MAP, MENU,
   * META, NOBR, NOFRAMES, OBJECT, OL, OPTION, P, PARAM,
   * PRE, SAMP, SCRIPT, SELECT, SMALL, SPAN, STRIKE, S,
   * STRONG, STYLE, SUB, SUP, TABLE, TD, TEXTAREA,
   * TH, TITLE, TR, TT, U, UL, VAR}.  If the given
   * name does not represent one of the well-known tags, then
   * <code>null</code> will be returned.
   *
   * @param tagName the <code>String</code> name requested
   * @return a tag constant corresponding to the <code>tagName</code>, or <code>null</code> if not
   * found
   */
  public static Tag getTag(String tagName) {

    Tag t = tagHashtable.get(tagName);
    return (t == null ? null : t);
  }

  /**
   * Returns the HTML <code>Tag</code> associated with the
   * <code>StyleConstants</code> key <code>sc</code>.
   * If no matching <code>Tag</code> is found, returns
   * <code>null</code>.
   *
   * @param sc the <code>StyleConstants</code> key
   * @return tag which corresponds to <code>sc</code>, or <code>null</code> if not found
   */
  static Tag getTagForStyleConstantsKey(StyleConstants sc) {
    return scMapping.get(sc);
  }

  /**
   * Fetches an integer attribute value.  Attribute values
   * are stored as a string, and this is a convenience method
   * to convert to an actual integer.
   *
   * @param attr the set of attributes to use to try to fetch a value
   * @param key the key to use to fetch the value
   * @param def the default value to use if the attribute isn't defined or there is an error
   * converting to an integer
   */
  public static int getIntegerAttributeValue(AttributeSet attr,
      Attribute key, int def) {
    int value = def;
    String istr = (String) attr.getAttribute(key);
    if (istr != null) {
      try {
        value = Integer.valueOf(istr).intValue();
      } catch (NumberFormatException e) {
        value = def;
      }
    }
    return value;
  }

  //  This is used in cases where the value for the attribute has not
  //  been specified.
  //
  public static final String NULL_ATTRIBUTE_VALUE = "#DEFAULT";

  // size determined similar to size of tagHashtable
  private static final Hashtable<String, Attribute> attHashtable = new Hashtable<String, Attribute>(
      77);

  static {

    for (int i = 0; i < Attribute.allAttributes.length; i++) {
      attHashtable.put(Attribute.allAttributes[i].toString(), Attribute.allAttributes[i]);
    }
  }

  /**
   * Returns the set of HTML attributes recognized.
   *
   * @return the set of HTML attributes recognized
   */
  public static Attribute[] getAllAttributeKeys() {
    Attribute[] attributes = new Attribute[Attribute.allAttributes.length];
    System.arraycopy(Attribute.allAttributes, 0,
        attributes, 0, Attribute.allAttributes.length);
    return attributes;
  }

  /**
   * Fetches an attribute constant for a well-known attribute name
   * (i.e. one of the attributes in the set {FACE, COMMENT, SIZE,
   * COLOR, CLEAR, BACKGROUND, BGCOLOR, TEXT, LINK, VLINK, ALINK,
   * WIDTH, HEIGHT, ALIGN, NAME, HREF, REL, REV, TITLE, TARGET,
   * SHAPE, COORDS, ISMAP, NOHREF, ALT, ID, SRC, HSPACE, VSPACE,
   * USEMAP, LOWSRC, CODEBASE, CODE, ARCHIVE, VALUE, VALUETYPE,
   * TYPE, CLASS, STYLE, LANG, DIR, DECLARE, CLASSID, DATA, CODETYPE,
   * STANDBY, BORDER, SHAPES, NOSHADE, COMPACT, START, ACTION, METHOD,
   * ENCTYPE, CHECKED, MAXLENGTH, MULTIPLE, SELECTED, ROWS, COLS,
   * DUMMY, CELLSPACING, CELLPADDING, VALIGN, HALIGN, NOWRAP, ROWSPAN,
   * COLSPAN, PROMPT, HTTPEQUIV, CONTENT, LANGUAGE, VERSION, N,
   * FRAMEBORDER, MARGINWIDTH, MARGINHEIGHT, SCROLLING, NORESIZE,
   * MEDIA, ENDTAG}).
   * If the given name does not represent one of the well-known attributes,
   * then <code>null</code> will be returned.
   *
   * @param attName the <code>String</code> requested
   * @return the <code>Attribute</code> corresponding to <code>attName</code>
   */
  public static Attribute getAttributeKey(String attName) {
    Attribute a = attHashtable.get(attName);
    if (a == null) {
      return null;
    }
    return a;
  }

}
